Today she is in Starship children's hospital in Auckland, unable to move or talk because of an unknown brain disease.

The Carterton community have rallied to support the 10-year-old, who played hockey, Rippa rugby and athletics before she was struck down by the mystery illness just over a month ago.

As Grace's parents, Stephen and Tracy, maintain a vigil by their daughter's bed at Starship, friends and supporters in Carterton have begun a trust to raise money for the family of six.

The Grace Yeats Trust hopes to raise $50,000.

"Grace will soon need to start intensive rehabilitation before she and her family can return to Carterton to start the long journey back to normal life," says a poster on the Carterton Information Centre website.

Mrs Yeats, a Plunket nurse who is the Carterton co-ordinator for children's charity Bellyful, is likely to have to take a year off work to look after Grace. Bellyful provide free meals and support for new mums and struggling families.

Trust spokesman Jonathan Tanner said Grace was a sporty, active child, who was quiet and had a dry sense of humour. But she had lost the ability to walk and talk as a result of the brain condition, which has not yet been diagnosed.

She had come home from school with a headache and was taken to hospital in Masterton, then flown to Starship early the next day.

Her "amazing" family were coping as well as could be expected, he said, and were being "really well looked after" by Starship and Ronald McDonald House.

Grace was a pupil at St Mary's School, and news of her illness was broken to pupils by principal Deirdre O'Flynn in a newsletter.

"Our thoughts and prayers are with her and her family ... It is heart-warming to see and hear the response from so many people who want to help in some way."

Yesterday, expressions of sympathy and offers of help had flooded the trust's Facebook page.

"How do we donate from Australia?

"I am from Masterton originally and would love to help this poor wee girl and her family in some way. Please let me know," wrote Abby Esler.

"They are a very special family and we have been on their heartbreaking journey with them this far," Sue Reid added. "It is a wonderful and kind gesture of Carterton community."

The level of support had been both "encouraging, and very overwhelming", trust organiser Jacqui Geange replied.